There is a great deal of misinformation about the Jhānas floating around in the Buddhist world today. My research has turned up no less than 25 different states that are identified by the word Jhāna in the ancient Pali literature:

Those who are fans of the Visuddhimagga tend to roll all these 25 different states into the 8 states matching the descriptions of the Jhānas given in the Visuddhimagga. Of course there is a precedent for doing so  the Visuddhimagga makes the same assumption. But a careful reading of the suttas, the Abhidhamma, and the Visuddhimagga clearly indicates that these are 25 different states.

Additionally there are other, more modern descriptions of states that go by the name Jhāna:

4 Vipassana Jhānas 4 Pure Land Jhānas
4 Path Moments are somethimes referred to as Supermundane Jhānas
1 Cessation experience that is sometimes referred to as the 9th Jhāna

This gives a total of 38 different states that are called by some form of the name Jhāna.

Unfortunately, most people who know anything about the Jhānas, assume that the states they have learned about or experienced are the only states that qualify for the name Jhāna. However, the Buddha was not practicing the states given in the Visuddhimagga; the monks at the time of the writing of the Visuddhimagga were not practicing the states described in the suttas. This difference among collections of states referred to as Jhānas is not just my opinion  see the writings of Thanissaro Bhikkhu (2011), Rod Bucknell (1993) and particularly Richard Shankman (2008).

What follows are the details of some of these other states that are referred to as "Jhānas:"